Urinary analysis of 16(5alpha)-androsten-3alpha-ol by gas chromatography/combustion/isotope ratio mass spectrometry: implications in anti-doping analysis.
J Chromatogr B Analyt Technol Biomed Life Sci
; 810(1): 157-64, 2004 Oct 15.
Article
en En
| MEDLINE
| ID: mdl-15358320
We present a method for the analysis of urinary 16(5alpha)-androsten-3alpha-ol together with 5beta-pregnane-3alpha,20alpha-diol and four testosterone metabolites: androsterone (Andro), etiocholanolone (Etio), 5alpha-androstane-3alpha,17beta-diol (5alphaA), 5beta-androstane-3alpha,17beta-diol (5betaA) by means of gas chromatography/combustion/isotopic ratio mass spectrometry (GC/C/IRMS). The within-assay and between-assay precision S.D.s of the investigated steroids were lower than 0.3 and 0.6 per thousand, respectively. A comparative study on a population composed of 20 subjects has shown that the differences of the intra-individual delta(13)C-values for 16(5alpha)-androsten-3alpha-ol and 5beta-pregnane-3alpha,20alpha-diol are less than 0.9 per thousand. Thereafter, the method has been applied in the frame of an excretion study following oral ingestion of 50 mg DHEA initially and oral ingestion of 50mg pregnenolone 48 h later. Our findings show that administration of DHEA does not affect the isotopic ratio values of 16(5alpha)-androsten-3alpha-ol and 5beta-pregnane-3alpha,20alpha-diol, whereas the isotopic ratio values of 5beta-pregnane-3alpha,20alpha-diol vary by more 5 per thousand upon ingestion of pregnenolone. We have observed delta(13)C-value changes lower than 1 per thousand for 16(5alpha)-androsten-3alpha-ol, though pregnenolone is a precursor of the 16-ene steroids. In contrast to 5beta-pregnane-3alpha,20alpha-diol, the 16-ene steroid may be used as an endogenous reference compound when pregnenolone is administered.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Doping en los Deportes
/
Androstenoles
Límite:
Humans
Idioma:
En
Revista:
J Chromatogr B Analyt Technol Biomed Life Sci
Asunto de la revista:
ENGENHARIA BIOMEDICA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Suiza
Pais de publicación:
Países Bajos